diff --git a/test/Regex.java b/test/Regex.java
index 44157d369e..48836cfe38 100644
--- a/test/Regex.java
+++ b/test/Regex.java
@@ -61,5 +61,6 @@ public class Regex {
     expectGroups("a|(b|c)", "c", "c");
     expectGroups("(?=a)a", "a");
     expectGroups(".*(o)(?<=[A-Z][a-z]*)", "Hello", "o");
+    expectNoMatch("(?!a).", "a");
   }
 }
diff --git a/test/regex/Compiler.java b/test/regex/Compiler.java
index 6967e542ba..e109be63bf 100644
--- a/test/regex/Compiler.java
+++ b/test/regex/Compiler.java
@@ -228,10 +228,11 @@ class Compiler implements PikeVMOpcodes {
 
   private class Lookaround extends Expression {
     private final Group group = new Group(false, null);
-    private final boolean forward;
+    private final boolean forward, negative;
 
-    public Lookaround(boolean forward) {
+    public Lookaround(boolean forward, boolean negative) {
       this.forward = forward;
+      this.negative = negative;
     }
 
     @Override
@@ -240,7 +241,9 @@ class Compiler implements PikeVMOpcodes {
       if (!forward) {
         vm.reverse();
       }
-      output.add(forward ? LOOKAHEAD : LOOKBEHIND);
+      output.add(forward ?
+        (negative ? NEGATIVE_LOOKAHEAD : LOOKAHEAD) :
+        (negative ? NEGATIVE_LOOKAHEAD : LOOKBEHIND));
       output.add(output.addLookaround(vm));
     }
   }
@@ -327,9 +330,10 @@ class Compiler implements PikeVMOpcodes {
           case ':':
             capturing = false;
             break;
+          case '!':
           case '=': {
             capturing = false;
-            Lookaround lookaround = new Lookaround(lookAhead);
+            Lookaround lookaround = new Lookaround(lookAhead, c == '!');
             current.push(lookaround);
             groups.push(lookaround.group);
             continue;
diff --git a/test/regex/PikeVM.java b/test/regex/PikeVM.java
index d0bd453d27..0888cdaa87 100644
--- a/test/regex/PikeVM.java
+++ b/test/regex/PikeVM.java
@@ -358,6 +358,18 @@ class PikeVM implements PikeVMOpcodes {
             current.queueImmediately(pc, pc + 2, false);
           }
           break;
+        case NEGATIVE_LOOKAHEAD:
+          if (!lookarounds[program[pc + 1]].matches(characters,
+              i, characters.length, true, false, null)) {
+            current.queueImmediately(pc, pc + 2, false);
+          }
+          break;
+        case NEGATIVE_LOOKBEHIND:
+          if (!lookarounds[program[pc + 1]].matches(characters,
+              i - 1, -1, true, false, null)) {
+            current.queueImmediately(pc, pc + 2, false);
+          }
+          break;
         /* immediate opcodes, i.e. thread continues within the same step */
         case SAVE_OFFSET:
           if (result != null) {
diff --git a/test/regex/PikeVMOpcodes.java b/test/regex/PikeVMOpcodes.java
index acd67cc2fd..53aaa4c5ed 100644
--- a/test/regex/PikeVMOpcodes.java
+++ b/test/regex/PikeVMOpcodes.java
@@ -26,6 +26,8 @@ interface PikeVMOpcodes {
 
   final static int LOOKAHEAD = -30;
   final static int LOOKBEHIND = -31;
+  final static int NEGATIVE_LOOKAHEAD = -32;
+  final static int NEGATIVE_LOOKBEHIND = -33;
 
   final static int SAVE_OFFSET = -40;